Theodore Ts'o 9dd75f1f1a ext4: fix nomblk_io_submit option so it correctly converts uninit blocks
Bug discovered by Jan Kara:

Finally, commit 1449032be17abb69116dbc393f67ceb8bd034f92 returned back
the old IO submission code but apparently it forgot to return the old
handling of uninitialized buffers so we unconditionnaly call
block_write_full_page() without specifying end_io function. So AFAICS
we never convert unwritten extents to written in some cases. For
example when I mount the fs as: mount -t ext4 -o
nomblk_io_submit,dioread_nolock /dev/ubdb /mnt and do
        int fd = open(argv[1], O_RDWR | O_CREAT | O_TRUNC, 0600);
        char buf[1024];
        memset(buf, 'a', sizeof(buf));
        fallocate(fd, 0, 0, 16384);
        write(fd, buf, sizeof(buf));

I get a file full of zeros (after remounting the filesystem so that
pagecache is dropped) instead of seeing the first KB contain 'a's.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2011-08-13 12:58:21 -04:00
..
2011-03-31 11:26:23 -03:00
2011-03-31 11:26:23 -03:00
2011-05-19 16:55:28 +09:30
2011-07-27 22:21:58 -04:00
2011-07-25 21:00:19 -07:00
2011-07-22 19:42:12 -04:00
2011-03-31 11:26:23 -03:00
2011-07-26 16:49:47 -07:00
2011-07-26 16:49:47 -07:00
2011-07-26 13:05:28 -04:00
2011-01-07 17:50:26 +11:00
2011-03-10 08:52:07 +01:00
2011-04-14 16:06:56 -07:00
2011-07-26 16:49:47 -07:00
2011-07-26 16:49:47 -07:00
2011-07-26 16:49:47 -07:00
2011-03-21 00:16:08 -04:00
2011-07-20 20:23:19 -04:00
2011-05-26 10:01:43 -06:00
2011-01-07 17:50:33 +11:00
2011-07-25 20:57:11 -07:00
2011-08-03 14:25:24 -10:00
2011-03-14 09:15:28 -04:00